Registration mechanism and method

ABSTRACT

A registration mechanism has a datum unit and a bolster movable toward and away from the datum unit. First, second, and third pins are mounted to the bolster. At least one spring resiliently biases the pins outward from the bolster. A pallet is supported by the pins between the bolster and datum unit. The pallet has first, second, and third sockets aligned with respective pins. The pallet has a registering face facing the datum unit. The registering face is disposed opposite the sockets. The pallet is movable by the bolster toward the datum unit from a lowered position. In the lowered position, the registering face is spaced from the datum unit and respective pins and sockets are spaced apart. In a first intermediate position, the registering face is spaced from the datum unit, and the sockets rest freely on respective pins. In a second intermediate position, respective sockets and pins are pressed together in partial counteraction of the resilient biasing. In a raised position, the registering face and datum unit are a clamped together and the sockets are immobilized relative to the pins.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly assigned, U.S. patent application Ser. No.09/464,555, now U.S. Pat. No. 6,354,431, entitled: DARK BOX-TRANSFERAPPARATUS AND MANUFACTURING SYSTEM, filed in the names of MichaelDeCecca, Joseph A. Watkins, and Duane B. Kirk each of which is assignedto the assignee of this application.

FIELD OF THE INVENTION

The invention relates to positioning equipment and methods formanufacturing and more particularly relates to a registration mechanismand method.

BACKGROUND OF THE INVENTION

A variety of procedures are known in which one-time use cameras areloaded with film, and the film is prewound in the dark. An example ofthis kind of procedure is disclosed in U.S. Pat. No. 5,689,876. Duringfilm loading, a onetime use camera frame assembly, that is, a camera orincomplete camera subunit, is moved through a series of workstations bya rotary turntable or a conveyor. A dark box encloses the film loadingworkstations. Camera frame assemblies enter and leave the dark boxthrough light-lock doors. Dark conditions are maintained during filmloading steps until the camera frame assemblies are light-tightly closedby installation of camera backs.

For film loading, accurate positioning of the camera frame assemblies inthe workstations is critical. Rapid movement from station to station ishighly desirable. Accurate positioning of the camera frame assembliesduring transit between workstations is not important. U.S. Pat. No.4,331,229 discloses a manufacturing machine in which pallets are movedfrom the station to station on a conveyor belt. At each station, thepallet is lifted from the belt and accurately positioned for access bythe tooling of that workstation. The manufacturing machine of thispatent provides accurate positioning at the workstations and can providerapid movement from station the station. The manufacturing machine hasthe shortcoming; however, that exacting measures must be takenindependently, at each station, to insurer accurate positioning. Thismay also be a strength, in general use under lighted conditions, sinceit would appear that a workstation could be serviced without necessarilydisaccommodating the remainder of the manufacturing machine. Darkconditions would make this impractical, since use of light duringservicing would avert usage of all the workstations.

A variety of different apparatus and methods are known for transportingand registering pallets and workpieces, such as U.S. Pat. Nos.3,888,341; 4,148,400; 4,201,284; 4,394,897; 4,850,102; 4,854,532;5,058,251; 5,062,188; 5,167,589; 5,197,172; 5,226,211; and 5,242,043.Features disclosed in one or more of these patents include use of atransfer bar, pallet clamping, and pallet locating using multiple,orthogonally arranged support points. Various of the disclosed deviceshave a number of shortcomings, such as: complexity; excess moving massthat is necessary for a high weight carrying capacity, but is excessivefor light, rapid manufacturing; overconstrained registration mechanismsrequiring more than a minimum of precision parts, and pallet movementsystems that require precision parts that are subject to high rates ofwear during use.

It would thus be desirable to provide an improved registration mechanismand method which is simple, not overconstrained and requires arelatively low number of precision parts.

SUMMARY OF THE INVENTION

The invention is defined by the claims. The invention, in some of itsbroader aspects, provides a registration mechanism that has a datum unitand a bolster movable toward and away from the datum unit. First,second, and third pins are mounted to the bolster. At least one springresiliently biases the pins outward from the bolster. A pallet issupported by the pins between the bolster and datum unit. The pallet hasfirst, second, and third sockets aligned with respective pins. Thepallet has a registering face facing the datum unit. The registeringface is disposed opposite the sockets. The pallet is movable by thebolster toward the datum unit from a lowered position. In the loweredposition, the registering face is spaced from the datum unit andrespective pins and sockets are spaced apart. In a first intermediateposition, the registering face is spaced from the datum unit, and thesockets rest freely on respective pins. In a second intermediateposition, respective sockets and pins are pressed together in partialcounteraction of the resilient biasing. In a raised position, theregistering face and datum unit are clamped together and the sockets areimmobilized relative to the pins.

It is an advantageous effect of at least some of the embodiments of theinvention that an improved film loading apparatus is provided which isrelatively quick and easy to set up and in which camera frame assembliescan be rapidly moved between workstations and accurately positioned inworkstations.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be better understood by reference to the followingdescription of an embodiment of the invention taken in conjunction withthe accompanying figures wherein:

FIG. 1 is a perspective view of the transfer and registration apparatus.A single pallet is illustrated in one of the cradles of the apparatus.The housing is not shown and infeed and outfeed conveyors are partiallycut-away.

FIG. 2 is a partial enlargement of the infeed end of the apparatus ofFIG. 1.

FIG. 3 is a partial enlargement of part of the middle section of theapparatus of FIG. 1. The registration surface defined by the datum padsis indicated by a dashed line. The alignment surface defined by thedatum pads is indicated by a dot-dash line.

FIG. 4 is a partial enlargement of the pallet and another part of themiddle section of the apparatus of FIG. 1.

FIG. 5 is a partial enlargement of the outfeed end of the apparatus ofFIG. 1.

FIG. 6 is a perspective view of the apparatus of FIG. 1 showing thehousing.

FIG. 7 is a partial enlargement of the infeed end of the apparatus ofFIG. 6 with the housing partially cut-away.

FIG. 8 is a partial enlargement of the outfeed end of the apparatus ofFIG. 6 with the housing partially cut-away.

FIG. 9 is a transverse (cross-track) cross-sectional view of theapparatus of FIG. 6 showing one of the elevators. The up and downpositions of a pallet are indicated diagrammatically by a solid linerectangle and dashed line rectangle, respectively.

FIG. 10 is a diagrammatical top view of another embodiment of thetransfer and registration apparatus. Pallets are indicated by dashedlines.

FIG. 11 is a semi-diagrammatical top view corresponding to a partialenlargement of the view of FIG. 10.

FIG. 12A is a diagrammatical perspective view of part of the apparatusof FIG. 9. Two workstations are shown by dashed lines having largerdashes. The boundaries of the indexing sites and registration siteswithin the workstations are indicated by dashed lines having smallerdashes. The transport, bolster, and table are shown cut-away.

FIG. 12B is another diagrammatical perspective view of part of theapparatus of FIG. 9 showing the work device area of the apparatus.

FIG. 13 is a perspective view of another embodiment of the transfer andregistration apparatus. The apparatus is seen from the infeed end.Pallets are in place in all the indexing sites. The housing and infeedand outfeed conveyors are not shown. The infeed elevator is in an upposition.

FIG. 14 is another perspective view of the apparatus of FIG. 13. Theapparatus is seen from the outfeed end. Pallets are in place in all theindexing sites. The housing and infeed and outfeed conveyors and maindrive belt are not shown. The infeed elevator is in an up position.

FIG. 15 is a top plan view of the apparatus of FIG. 14.

FIG. 16 is the same view as FIG. 14, but the datum units are not shown,the elevator is not shown, the belt is shown, and only one platen ispresent.

FIG. 17 is a transverse cross-sectional view of the apparatus of FIG.13. The cross-section extends through the centers of the first and thirdpins of one of the locating units. An alternative pallet is in place onthe locating unit. The bolster is in the raised position and therespective registering and registration faces are clamped together.

FIG. 18 is the same view as FIG. 14, except that only the locatingunits, bolster, and lifter are shown.

FIG. 19 is a schematic illustrating the mechanical coupling of thetransporter and lifter.

FIG. 20 is a partial cross-sectional view of a pallet and the first andsecond pins of a locating unit of the apparatus of FIG. 13, duringinitial movement of the bolster out of the lowered position.

FIG. 21 is the same view as FIG. 20 of another embodiment of theapparatus, showing the first pin of a locating unit and the respectivefirst socket of the pallet.

FIG. 22A is a partial cross-sectional view of another embodiment of theinvention, showing the third pin of a locating unit and the respectivethird socket of the pallet.

FIG. 22B is the same view as FIG. 22A of still another embodiment of theinvention.

FIGS. 23-28 are diagrammatical top view of alternative pallets of theapparatus.

FIGS. 29-32 are schematics of alternative embodiments of themanufacturing system of the invention.

FIGS. 33-38 are diagrammatical side views of the infeed end of theapparatus of FIG. 1 and illustrate, in sequence, the movement of apallet by the plow and elevator.

FIGS. 39-42 are diagrammatical transverse cross-sectional views of theapparatus of FIG. 13 and illustrate movement of the pallet and locatingunits when the bolster is moved from the lowered position, throughintermediate positions, to the raised position, respectively. Somedimensions are exaggerated for clarity.

FIG. 43 is a transverse cross-sectional view of the apparatus of FIG.13. The cross-section of an arch-shaped work device area defined by thetable is illustrated by a dashed line.

FIG. 44 is a partially cut-away perspective view of another embodimentof the registration mechanism.

FIG. 45 is a partially cut-away perspective view of another embodimentof the transfer apparatus.

FIGS. 46-49 are cross-sectional view of alternative datum pads.

DETAILED DESCRIPTION OF THE INVENTION

Referring initially to FIGS. 1-12B, the apparatus 10 provides bothtransfer and registration of workpieces 12, on pallets 11, in a sequenceof workstations 14. In preferred embodiments, the workpieces 12 arepalletized camera frame assemblies 12 a (shown in FIG. 11), into whichfilm is loaded, and the apparatus 10 includes a light-excludingenclosure or housing 16 that functions as a dark-box for theworkstations 14. Such embodiments are preferred, but are not limiting.For example, the apparatus 10 can be used with other types of workpieces12. The enclosure 16 can be eliminated if the work performed is notlight-sensitive. The workpieces 12 can be “non-palletized”, that is, theworkpieces 12 themselves can include a portion that acts as a pallet 11.The apparatus 10 can be modified to provide only transfer orregistration. The apparatus 10 can be limited to a single workstation14. It will be understood, from the embodiments discussed in detailherein, that like considerations apply to the other embodiments.

Referring now primarily to FIGS. 6-8 and 10, the housing 16 has a mainchamber 18 and light-locking entry and exit chambers 20,22 at either endthat lead into and out of the main chamber 18. The entry and exitchambers 20,22 each have spaced apart, light-tight, inner and outerdoors 24,26. (Doors 24,26 are each shown in open position in FIGS. 6-8)For each chamber 14,16, the doors 24,26 are movable one at a time toprevent admission of light. At the entry chamber 20, camera frameassemblies 12 a are moved through the outer door 24, and into a spaceenclosed by the entry chamber 20. The outer door 26 is then shut and theinner door 24 is opened for movement of the camera frame assemblies 12 ainto the main chamber 18. After film loading, the reverse of thisprocess is followed for the exit chamber 22.

In a particular embodiment shown in FIGS. 1-8, the housing 16 has main,entry, and exit chambers 18,20,22 and a pair of connecting tunnels 23connecting the entry and exit chambers 20,22 to the main chamber 18.Entry and exit conveyors 25,27 are disposed in the entry and exitchambers 20,22, respectively; and stub conveyors 29 extend from theentry and exit conveyors 25,27 to the main chamber 18. Adjoiningconveyors 25,29 and 29,27 are close together to provide an uninterruptedpath when the respective inner door 24 is open.

Referring now primarily to FIGS. 1-5, a table 28 has a support surface31 that is within the main chamber 18 and a main support 19 that may ormay not be in the main chamber 18. The remainder of the table 28 can bejoined to or within the main chamber 18. The table 28 has a pair ofparallel flanges 30. The flanges 30 are each joined to a table base 32that includes support surface 31. Each flange 30 has an upwardly facingleg 34 and an outwardly facing leg 35. The upwardly facing legs 34 arespaced apart by a uniform gap. The table base 32 can be immobile, but itis preferred that the table base 32 is a relatively light-weight supportstructure.

The table 28 has a sequence of datum units 36. Each datum unit 36 has asingle continuous datum pad 38 or is subdivided into two or moreseparated datum pads 38. It is preferred that datum pads 38 be joined toboth flanges 30. In a particular embodiment of the invention, each datumunit 36 has three datum pads 38, with two of the pads 38 located on oneof the flanges 30 and the third pad 38 located on the other flange 30.The datum pads 38 can be continuous with the rest of the table 28, butfor ease of manufacture and replacement after wear or damage, it ispreferred that each datum pad 38 be removably joined to the remainder ofthe table 28. When joined to the table 28, datum pads 38 are immobilerelative to the remainder of the table 28.

The datum pads 38 have opposed alignment and registration faces 40,42.It is highly preferred that each datum pad 38 has both an alignment face40 and a registration face 42 and that the alignment face 40 andregistration face 42 are permanently aligned. Faces 40,42 can havecurved or complex shapes, but are preferably flat or spherical, as shownin FIGS. 46-48. Threaded holes or other fastener subparts can be offsetor recessed, as can be seen in FIG. 3. Flat and parallel alignment andregistration faces 40,42 are convenient to work with during bothmanufacture and use of the apparatus 10. Remaining portions of datumpads 38 can be shaped as convenient. It is currently preferred thatdatum pads are immobile, however, datum pads can be gimballed as shownin FIG. 49.

The datum pads 38 are joined to the table 28 in a predeterminedarrangement such that the alignment faces 40 together define analignment surface 44 and the registration faces 42 together define aregistration surface 46. (With gimballed datum pads 38, the surfaces44,46 are defined when the pads are in a neutral position in which thesurfaces are aligned with travel and cross-track axes (discussedbelow).) The alignment and registration surfaces 44,46, each combine theshapes of the respective alignment and registration faces 40,42. In theapparatus shown in FIG. 3, the alignment surface 44 and the registrationsurface 46 are each planar and the registration surface underlies thealignment surface. Planar alignment and registration surfaces 44,46 areconvenient for apparatus set-up, but other, more complex shapes, such aslaterally stepped planes, can also be used.

Referring particularly to FIGS. 10-11, 12A-12B, and 43, the datum units36 also define a sequence of workstations 14. Each workstation 14(indicated in FIG. 12A by dashed lines having long dashes) has a devicespace 47 (coinciding with the workstation 14, except as indicated inFIG. 12A by dashed lines having short dashes) for one or more workdevices 48; a workstation indexing site 50, into which a pallet 11 isindexed during transport; and a registration site 52, which the pallet11 occupies as work is done on the workpiece 12 by the work device 48.It is preferred that workstations 14 do not overlap and are spaced at auniform pitch along the table 28. For simplicity, it is highly preferredthat the workstations 14 are all within the main chamber 18 of thehousing 16. Work devices 48 can be fully enclosed in the housing 16 orcan have portions extending outward through a wall of the housing 16(not shown) provided that adequate light blocking is present.

The work device 48, within a workstation 14, includes a tool 54 and anoperating unit 55 for the tool 54. The tool 54 of each work device 48 ismovable relative to the respective registration site 52 as required by aparticular manufacturing process. Suitable tools 54 for assembling filmbearing camera frame assemblies 12 a are well known to those of skill inthe art. For example as shown in FIG. 11, a pallet 11 has a first nest56 that closely receives a camera frame assembly 12 a, for a one-timeuse camera, in a predetermined alignment and a second nest 58 thatreceives a film unit 60. A first work device 48 a transfers the filmunit 60 into the camera frame assembly 12 a and a second work device 48b prepares a filmstrip 62 of the film unit 60 for winding. (Thepreparation illustrated in FIG. 11 is thrusting along the camera frameassembly.) A third work device 48 c then prewinds the filmstrip 62 thefilm unit 60 within the respective camera frame assembly 12 a.Convenient work devices for this purpose are disclosed in U.S. Pat. No.5,873,002.

The work device 48, within a workstation 14, is aligned with theregistration site 52 by being aligned with the alignment surface 44 ofthe respective datum unit 36. In the embodiments shown in the figures,this can be done by mounting the work device 48 directly to therespective alignment face or faces 40 using bolts or other fasteners.The datum pads 38 can fully support a work device 48 or can providepartial support or can be used just to align a separately supported workdevice 48. It is preferred that the work devices 48 are each mounted tothe table 28 in some manner.

A work device 48 does not have to be present in each workstation 14. Forexample, if a particular work device 48 is oversize, then all or part ofthe device space 47 of an adjoining workstation 14 can be used toprovide clearance. The device spaces 47 taken together form a workdevice area 61. The work device area 61 extends upward and laterallyoutward from the datum units 36. The work device area 61 defined by thetable 28 illustrated in FIG. 43 is arch-shaped and is illustrated by adashed line. The outer boundaries of the work device area 61 are amatter of convenience or are limited to the confines of the main chamber18 of the light-tight housing 16. Smaller work device areas 61 can beprovided, if desired, by limiting work devices 48 to one of the flanges30 of a table 28. If only one of the flanges 30 is used, then the otherflange 30 can be eliminated or reduced in size, except as required forstructural support. An arch-shaped work device area 61 is preferred,because this allows access by work devices from two sides and above andthus allows greater flexibility in placement of work devices 48.

Pallets 11 are moved along the table 28, from one indexing site 50 tothe next, by a transporter 64. In addition to the workstation indexingsites 50, the table 28 can also have auxiliary indexing sites 66 thatare not within workstations 14 and are used for other functions, such asan infeed indexing site 66 a for loading pallets 11 onto the transporter64 and an outfeed indexing site 66 b for unloading pallets 11 from thetransporter 64. The auxiliary indexing sites 66 are not in workstations14 and do not have corresponding registration sites 52.

Referring now mainly to FIGS. 1-5, the transporter 64 is aligned withthe table 28. The transporter 64 can be mounted to an underlyingfoundation or directly to the table 28. The transporter 64 occupiesspace only between the flanges 30 and under the surface 31 and is thusspaced from the work device area 61. The transporter 64 advances thepallets 11 longitudinally along the table 28 and incrementally past eachdatum unit 36. It is preferred that the transporter 64 utilizes anendless transport belt 68; however, other types of mechanism can beused, such as chains, motorized rollers, linear motors and the like, canalso be used. The endless transport belt 68 is currently preferred, forthe reasons that the belt 68 provides very economical use of space inthe apparatus 10. This is important for preferred embodiments, since thetransporter 64 has to function within the main chamber 18. The transportbelt 68 is also simple and easy to maintain. For convenience, theapparatus 10 is generally described herein in terms of an apparatus 10including a transport belt 68. It will be understood that likeconsiderations apply to apparatus 10 having other transporters 64.

The belt 68 has a forward run 70 and a return run 72. The forward run 70is aligned with the table 28 and is disposed between the flanges 30 ofthe table 28. (The return run 72 is also aligned with the table 28 inthe illustrated embodiments.) It is convenient if the forward run 70 ishorizontal, but other orientations can be used if appropriate holddowns(not illustrated) for pallets 11 and workpieces 12 are used. As a matterof convenience herein, the transfer apparatus 10 is described usingdirectional terms based on a horizontally disposed forward run 70. Thereturn run 72 of the transport belt 68 is not critical and can parallelthe forward run 70 vertically, as shown in the figures, or horizontally(not shown). The vertically paralleled return run 72 is preferred forreasons of compactness. The return run 72 can also follow a more complexpath, if desired. The forward run 70 advances in a direction indicatedby arrow 73 from an infeed end adjoining the entry chamber 20 to anoutfeed end adjoining the exit chamber 22.

The transport belt 68 has a sequence of cradles 74. Each cradle 74 isconfigured, when on the forward run 70, to receive a pallet 11. Thepallets 11 on the cradles 74 of the forward run 70 can each carry aworkpiece 12. During use, workpieces 12 can be present in each cradle 74of the forward run 70 or some cradles 74 can be left empty.

The cradles 74 receive the pallets 11 and can be adapted to match theconfiguration of particular pallets 11 or a generalized configurationthat can accommodate a variety of different pallets 11. For simplicity,it is generally convenient if, all pallets 11 in use on the apparatus 10at a particular time have the same configuration.

The pitch of the transport belt 68, that is, the spacing from cradle 74to cradle 74, matches the pitch of the indexing sites 50, the spacingfrom one indexing site 50 or 66 to the next. It is preferred that thecradles 74 have a longitudinal dimension, in the direction of advance ofthe forward run 70, that is only slightly larger than the longitudinaldimension, in the same direction, of the respective pallets 11. Thisminimizes the mass that must be moved and also reduces the size requiredfor the light-tight housing 16. To further minimize length of theforward run 70, in the embodiments shown in the figures, the forward run70 of the transport belt 68 has a length that closely matches a multipleof the length of the cradles 74 in the same direction.

Referring to FIGS. 1-5, the belt 68 has a continuous band 77 of flexiblematerial or chain and a sequence of regularly spaced lugs 78, whichdelineate the cradles 74. Each lug 78 has one or more protuberances 78a, which protrude outward from the band 77. The pallets 11 rest looselyin the respective cradles 74 under the action of gravity, such that thelugs 78 butt against a longitudinal end 80 of a pallet 11 and push alongthe pallet 11 when the belt 68 is advanced.

In the embodiments illustrated, the pallets 11 are removable. Thepallets 11 are each placed in a cradle 74 at the entry end of theforward run 70 and are taken out of that cradle 74 at the exit end. Thetransport belt 68 can, alternatively, have pallets that are notremovable from the belt (not illustrated), or can transport workpiecesthat themselves incorporate non-removable pallets.

The transporter 64 defines vertically-oriented locating unit passageways76 adjacent each of the cradles 74 in the workstations 14. The pallets11 in the workstations 14 overlie the respective locating unitpassageways 76. In the embodiments shown in the figures, a pair ofrectangular passageways 76 adjoin either side of the cradles 74 in theworkstations 14.

During use, the transport belt 68 incrementally steps the cradles 74,and carried pallets 11 and workpieces 12, from indexing site to indexingsite along the table. A drive 82 is actuated and deactuated to move thebelt 68. Timing of the actuation and deactuation can be based on anyconvenient means, such as mechanical switches, or sensors and aprogrammed electronic computer (not illustrated).

The manner of feeding the pallets 11 in and out is not critical as longas the pallets 11 can be placed in and removed from the transporter 64at a reasonable speed and without mispositioning. The feeding can bemanual or can use automated equipment. Referring to FIGS. 1-2, 9-10, and19, in some of the embodiments shown, at the infeed and outfeed ends ofthe belt 68, a pallet 11 is moved onto and off of the forward run 70,respectively. A stub-conveyor 29 moves pallets from the entry chamber 20to an entry buffer 85 within the main chamber 18 adjoining the infeedindexing station 66 a. A stop 86 holds the pallets 11 back until thetransporter 64 has advanced a pallet 11 out of the infeed indexing site66 a to the first of the workstation indexing sites 50 and the elevator88 at the infeed indexing site 66 a has moved to an up position.

The elevator 88 has a pair of channels 90 (most easily seen in FIG. 9)that adjoin the belt 68 at either side. The channels 90 are supported bya hoist 92 having a pair of air cylinders 94 joined in common to asource of compressed air 96. The elevator 88 is movable between an upposition and a down position. In the up position, the elevator 88 isvertically aligned with the stub-conveyor 29. In the down position, theelevator 88 is below the level of the belt 68.

Referring now particularly to FIGS. 1-2, 5, 10, 19, and 33-38, a feedmechanism 98 adjoins the infeed indexing station 66 a on one side andextends along part of the entry buffer 85. The feed mechanism 98 has aslider 100 that includes a chassis 102 that reciprocates parallel to thedirection of pallet advance indicated by arrow 73. The slider 100 has aplow 104 that is mounted to the chassis 102 and pivotable about an axis106 that is transverse to the pallet advance direction 73. The plow 104is biased downward, toward the table 28 by a spring 108. The plow 104has a forward edge 110 that is vertically aligned and parallel to thelongitudinal ends 80 of the pallets 11 in the entry buffer 85 and in thecradle 74. The plow 104 has a return edge 112 that is angled diagonallyupward and outward from the table 28, in a direction transverse, andpreferably perpendicular, to the pivot axis 106 of the plow 104.

Referring now particularly to FIGS. 2 and 33-38, when the transporter 64has advanced a pallet 11 out of the infeed indexing site 66 a to thefirst of the workstation indexing sites 50 and the elevator 88 has movedto the up position, the stop 86 is retracted and the plow 104 is moved,in the direction of arrow 114 in FIG. 33, from an inward positionadjoining the infeed indexing site 66 a to an outward position adjoiningthe entry buffer 85. The plow 104 enters the entry buffer 85 and thereturn edge 112 comes into contact with the waiting pallet 11. The plow104 pivots about axis 106 in the direction indicated by arrow 116 inFIG. 34. The plow 104 is moved through the entry buffer 85 with thereturn edge riding on the pallet 11, as indicated in FIG. 35, until theforward edge 110 passes the outward longitudinal end 80 of the pallet11. The plow 104 then rotates in the direction of arrow 118 in FIG. 36and the forward edge 110 of the plow 104 comes into contact with theouter longitudinal end 80 of the pallet 11. The plow 104 is then movedback toward the table in the direction of arrow 120 in FIG. 37. Thepallet 11 is pushed onto the elevator 88 and the elevator 88 is loweredin the direction of arrow 122 in FIG. 38 until the pallet 11 rests onthe belt 68.

Referring now to FIGS. 5 and 10, the apparatus 10 has an elevator 88 andfeed mechanism 98 adjoining the outfeed indexing site 66 b that arestructured and operate in the same manner as the elevator 88 and feedmechanism 98 at the infeed indexing site 66 a.

Referring now particularly to FIGS. 1, 10-12B, and 17-19, an elongatebolster 124 is mounted in alignment with the workstations 14 of thetable 28 and with the transporter 64. The bolster 124 has a series ofbolster segments 126 aligned with individual workstations 14. A locatingunit 128 is disposed between each bolster segment 126 and the respectivepallet 11. The bolster segment 126 and pallet 11 temporarily associatedwith an individual locating unit 128 are also referred to collectivelyherein as a “bolster segment-pallet pair”. The bolster 124 is joined toa lifter 132 which reciprocates the bolster segment-pallet pairs 130between a lowered position and a raised position relative to the datumunits 36 of the table 28. The bolster 124 lifts pallets 11, withinworkstations 14, from indexing sites 50 to registration sites 52. Thepallets 11 in the workstation indexing sites 50 are all lifted, held inposition, and lowered by the bolster 124 simultaneously. The bolster 124is rigid, such that the movement of the bolster 124, and lifted pallets11, is the same for all the bolster segments 126. The length of thebolster 124 and the number of workstation indexing sites 50 present canbe varied, subject to practical limitations, such as available space,and the mass of the bolster 124. Eight intermediate indexing sites 50are illustrated in FIG. 1. The bolsters 124 shown in the figures areused with linear transporters. Bolsters 124 and transporters can becurved or circular; however, linear transporters 64 and bolsters 124have the advantages of maximizing available space for work devices 48 onboth sides of the table 28 and providing workstations 14 that arerectangular in outline rather than sector-shaped.

The bolster 124 and the lifter 132 are configured such that the relativepositions of the table 28 and the bolster 124, are precise withinpredetermined tolerances and are accurately reproduced during eachreciprocation of the bolster 124. Within these limitations, the path ofthe bolster 124 is not critical. For simplicity, it is preferred thatthe reciprocation of the bolster 124 is an up-and-down motion in thedirection perpendicular to the direction of pallet travel. This kind ofmotion is preferred, because required mechanical components arerelatively simple and close tolerances are relatively easy to obtain.The bolster 124 is not, however, limited to vertical movement. Thebolster 124 could move horizontally rather than vertically or in someother direction, or could rotate about a fixed axis toward and away fromthe datum units 36, or could move vertically and simultaneously rotateabout one or more axes (not illustrated). These alternatives would verylikely add complexity. For example, non-vertical movements would likelynecessitate holddowns, rather than gravity, to keep pallets in place.

The bolster 124 is mounted under the forward run 70 of the transportbelt 68. The bolster 124 is shaped to accommodate the spatialconstraints imposed by the table 28 and the transport belt 68. In theembodiments shown in figures, the bolster 124 has a pair of spaced apartright and left rails 134,136. Each rail adjoins a respective flange 30of the table 28. The rails 134,136 may or may not be directly joinedtogether. In the embodiments shown, the rails 134,136 are not directlyjoined to each other, but are aligned in fixed geometric relation toeach other and mechanically coupled together to move only in tandem.

The bolster 124 is moved between the lowered and raised positions,intermittently in synchrony with the movement of the cradles 74 of thetransport belt 68. The transport belt 68 is actuated and the pallets 11are transported to indexing sites 50 within workstations 14. Thetransport belt 68 is stopped and the bolster 124 is raised lifting thepallets 11. Work is performed on the workpieces 12. The bolster 124 isthen lowered letting down the pallets 11. The transporter 64 is againactuated, stepping the pallets 11 forward to the succeeding indexingsites 50, and the process continues.

The lifter 132 moves the bolster 124. A variety of different types oflifters 132 can be used, subject to the limitation that the bolster 124is moved as a unitary structure. For example, the lifter 132 can have aset of linear motion devices such as solenoids linked by a computerizedcontrol, or a set of commonly controlled hydraulic or pneumaticcylinders.

A mechanical lifter 132 is currently preferred. This lifter 132 has theadvantage of being relatively simple to set up and use, and very robust.The lifter 132 has two pair of lift arms 138. The number of pairs oflift arms 138 used is a matter of convenience and the support. Each liftarm 138 has one end joined to a respective rail 134 or 136. Members ofeach pair 138 are joined to right and left rails 134,136, respectively.Each lift arm 138 is slideably joined to the table 28 at a slide bushing140 (only the movable portion of slide bushing 140 is shown) and is ableto reciprocate relative to the table 28 in the same manner as thebolster 124. The term “bushing” is used herein broadly to refer tomechanical supports and is inclusive of both traditional bushings andalso of bearings and other types of support. The slide bushings 140 arealigned with the table 28 and are preferably mounted to the table 28.The other end of each lift arm 138 is supported on an eccentric 142. Theeccentrics 142 are oval wheels that are all aligned with each other. Theeccentrics 142 for each pair of lift arms 138 are coaxial and are fixedto a common axle 144. The axles 144 are mounted in rotary bushings 145aligned with and, preferably mounted to, the table 28.

Synchronization of the lifter 132 and bolster 124 with the transportbelt 68 can be provided by a controller including sensors and amicroprocessor (not shown), or mechanically, or by other means. Forexample, servomotors could be used to provide the movements, withsynchronization and control provided by a microprocessor or the like.Suitable components, including gear trains, power sources, and motiontransfer devices are within the knowledge of those of skill in the art.

In the embodiment shown in the figures, synchrony between the transportbelt 68 and the bolster 124 is provided by mechanical coupling. As shownin FIG. 19, a power source 146, such as an electric motor, drives aindexer 148. A toothed belt 150 connects the indexer 148 to a sprocketwheel 152 on the lifter 132. The sprocket wheel 152 drives one of theaxles 144, directly or through a gear unit 154. A pair of the eccentrics142 are joined to the axle 144 and rotate with the axle 144. Lifter arms138 can ride directly on respective eccentrics 142 or can be supportedon rollers 156. The other axle 144 can be driven by a second toothedbelt 150 and sprocket 152 (not shown in FIG. 19).

Another toothed belt 158 connects the indexer 148 to a first rim ofdouble sprocket 160 of the transporter 64. Double sprocket 160 has asecond rim that is meshed with teeth of the belt 68.

There is a signal path 162 between the indexer 148 and the compressedair source 96, which causes the compressed air source 96 to move theelevator channels 90 in synchrony with the stepped advancements of thetransporter 64. The nature of the signal provided on the signal path 162is not critical and can be, for example, electrical or mechanical orpneumatic. The elevator can also be mechanically driven by aneccentric-axle-gear train mechanism like that described above inrelation to the lifters.

Referring now to FIGS. 20-28 and 39-42, as the bolster 124 is moved outfrom the lowered position, the pallets 11 are lifted out of respectivecradles 74, to a series of intermediate positions, and then to theraised position. In the lowered position, the pallets 11 are each fullysupported by a respective cradle 74 of the transporter 64. In theintermediate and raised positions, the pallets 11 are supported by therespective locating units 128, which are supported, in turn, by therespective bolster segments 126.

The locating units 128 are ganged, that is, the locating units 128 arepositioned on the bolster 124 to act concurrently on the pallets 11 inthe workstations 14. The locating units 128 orient the pallets 11, intwo or more directions relative to the bolster 124, as the pallets 11are lifted. In the raised position, the locating units 128 clampregistering faces 164 of the pallets 11 against the respectiveregistration faces 42. When the bolster 124 is in the raised position,the pallets 11 each define the registration sites 52 within theworkstations 14. The registration sites 52 have predetermined spatialrelationships to the respective datum units 36 and aligned work devices48.

The registering faces 164 are disposed opposite the locating units 128;in the embodiments shown in the Figures, on the top sides of the pallets11. The registering faces 164 are spaced from the registration faces 42of the datum pads 38 until the pallets 11 enter the raised position.Each registering face 164 is shaped to closely seat against therespective registration face 42 and is preferably complementary inshape. As with the registration surfaces 46, it is preferred that theregistering faces 164 are flat and are uniform from pallet to pallet.

The locating units 128 each have one or more support members or pins166. The pins 166 protrude upward relative to the top of the bolster 124and downward relative to the pallets 11. It is preferred that the pins166 are small and that three are used. With a bolster 124 having a pairof rails 134,136, it is preferred that pins 166 are provided on each ofthe rails 134,136.

The pins 166 each have a free end 168 and a mounted end 170. The mountedends 170 are joined to mounts 174 of a respective segment 126 of thebolster 124. The free ends 168 engage sockets 172 of respective pallets11. The bolster segment 126 and pallet 11 temporarily associated with anindividual locating unit 128 define a bolster segment-pallet pair 130that includes sockets 172 for the free ends 168 and mounts 174 for themounted ends 170 of the pins 166 of the locating unit 128. The mountedends 170 are joined to the mounts 174 so as to not disjoin when thepallets 11 are removed. The pins 166 can be permanently mounted in themounts 174, but are preferably mounted, by use of engaged threads (notshown) or the like, so as be easily replaceable when worn. The free ends168 engage and are freely removable from the sockets 172. Some or all ofthe mounts 174 can be provided in the pallets 11, but it is generallypreferred that the mounts 174 are provided in the bolster 124 and thesockets 172 in the pallets 11, since pins 166 joined to pallets 11 havea greater likelihood of suffering damage during use than pins 166 joinedto the bolster 124.

It is preferred that locating units 128 are biased in an outwarddirection from the respective pallet 11 or bolster segment 126 or both.The biasing reduces stresses on the pallets 11 and datum units 36, whenthey 11,36 are clamped together. It is also highly preferred that thepins 166 of the locating units 128 are biased outward from therespective registering faces 164. This outward biasing allows time forpins 166 to move against respective mounts 174 before the registeringand registration faces 164,42 lock together. In other words, each pallet11 starts in a lowered position, in which the registering face 164 ofthe pallet 11 and the registration face 42 of the respective datum unit36 are spaced apart and the respective said pins 166 and sockets 172 areloosely engaged or, preferably, spaced apart. The weight of the pallet11 is borne by the cradle 74. The pallet 11 is moved by the bolster 124toward the datum unit 36. The pallet 11 enters and moves through a firstintermediate position, in which the registering face 164 andregistration face 42 are spaced apart and the sockets 172 rest freely onrespective pins 166, with the weight of the pallet 11 borne by thebolster 124 rather than the cradle 74. The pallet 11 is then moved bythe bolster 124 through a second intermediate position, in which therespective sockets 172. and pins 166 are pressed together in partialcounteraction of the resilient biasing. The pallet 11 is next moved intoa raised position. The registering face 164 and registration face 42come into contact and are then clamped together. This immobilizes thepins 166 relative to respective sockets 172. It is highly preferred thatthe clamping force be applied to the pallet 11 solely through the pins166, as opposed to separate clamping members. This ensures thatpositioning of the pallet 11 on the pins 166 during movement into theraised position is not lost as the clamping force is applied. Biasingcan be provided by a single resilient member (not shown) shared by thepins 166 of the locating unit 128 or individual springs 176 can beprovided for each of the pins 166. Mechanical springs 176 are simple,but other kinds of springs 176 can be used, such as air springs orblocks of elastomer.

The locating units 128 each have first, second, and third pins 166 a,166b,166 c. The bolster segments 126 and pallets 11 have correspondingfirst, second, and third mounts 174 a,174 b,174 c, and sockets 172 a,172b,172 c, all respectively. The mounts 174 a, 174 b, 174 c defineparallel mount axes 180 a,180 b,180 c. For convenience the first,second, and third pins 166 a,166 b,166 c and respective first, second,and third mounts 174 a, 174 b, 174 c or first, second, and third sockets172 a, 172 b, 172 c are sometimes referred to as “pin-mount pairs” and“pin-socket pairs”. A first pin-mount pair 171 a includes a first pin166 a and the respective first mount 174 a. Second and third pin-mountpairs 171 b and 171 c include second and third pins 166 b,166 c andsecond and third mounts 174 b,174 c, all respectively. A firstpin-socket pair 173 a includes a first pin 166 a and the respectivefirst socket 172 a. Second and third pin-socket pairs 173 b and 173 cinclude second and third pins 166 b,166 c and second and third sockets172 b,172 c, all respectively. In a pin-socket pair, the pin and socketreferred to are in engagement and descriptions of the pin-socket pairmay not be applicable to the respective pin and socket when not engaged.

Two of the pins 166 of each locating unit 128 are mounted to the leftrail 134 of the bolster 124. The other pin 166 of each locating unit 128is mounted to the right rail 136 of the bolster 124. When the bolster124 is in the lowered position, the pins 166 are joined to the mounts174, facing the forward run 70 of the belt 68, and are spaced from therespective pallets 11. As the pallets 11 are lifted out of the cradles74, the pins 166 protrude through the locating unit passageways 76 andthe free ends 168 of the pins 166 move against the respective sockets172, under the action of gravity.

As illustrated, the mounted ends 170 of the pins 166 are slideablyretained within bores 178 in the bolster 124. The pins 166 areconstrained from lateral movement by the respective mounts 174 and arelimited to rotation. about and linear movement along mount axes 180which are parallel to directions of movement of the bolster 124 betweenthe raised and lowered positions. Individual springs 176 are disposed inthe bores 178 below the pins 166 and bias the pins 166 outward along themount axes 180 toward the respective pallets 11 and datum units 36.

The sockets 172 have upwardly sloping surfaces that are define openingsthat are larger than the free ends of the pins 166. The free ends 168 ofthe pins 166 ride along the corresponding sockets 172 orienting thepallets 11 when the bolster 124 is raised and the pins 166 engage therespective sockets 172. There is a vertical overlap between pins 166 andrespective sockets 172 in the lowered position. The transporter 64transports the pallets 11, such that this vertical overlap is providedwhen the pallets are in the lowered position. The dimensions andmovement of the transporter 64 are much less precise than the dimensionsof the locating units 128 and datum units 36 and the movement of thebolster 124. There is an advantage here. The datum units 36 do not moveduring use. The locating units 128 and bolster 124 only move linearly,up and down. The transporter 64 moves in a more complex manner than theother components and is more likely to exhibit wear, but a large amountof wear can be accommodated before the functionality of the transporteris degraded.

In particular embodiments of the invention, the free ends 168 of thepins 166 and the degrees of freedom of each pin-socket pair 173 a,173b,173 c differ. In those embodiments, the first pin 166 a has ahemispherical tip 186. The first socket 172 a is conical or cup-shapedand, preferably, has equal dimensions along the a cross-track axis 182and a travel axis 184. In the embodiment shown in FIG. 20, the socket isshaped like a cone joined to a narrow cylinder at its apex. The size ofthe first pin 166 a relative to the first socket 172 a can vary; withthe largest being that the first pin 166 a and first socket 172 a arefully complementary and the smallest being that the first pin 166 acomes to a point. (A pointed first pin 166 a is usable, but ephemeral,since the point quickly wears into a hemisphere.)

In those embodiments, the free end 168 of the first pin 166 a obstructsthe first socket 172 a from translating along orthogonal cross-track andtravel axes 182,184 that are perpendicular to the mount axis 180. (Mountaxes 180 are referred to individually herein. “Travel axis 182” and“cross-track axis 184” refer, in each case, to any of a series ofparallel axes extending in the same directions. The first socket 172 ais unobstructed for rotation about the first mount axis 180 a, with thefree end 168 in engagement with the first socket 172 a. The first socket172 a is also unobstructed for rotation about the cross-track and travelaxes 182,184 through a hemisphere centered on the first mount axis 180a, while in engagement with the first pin 166 a.

The second pin 166 b can have the shapes discussed above for the firstpin 166 a. The shapes of the first and second pins 166 a,166 b can bethe same or different. The second socket 172 b is an elongate,trough-shaped notch. In the embodiments shown in FIGS. 20 and 23-25, thenotch has a rectangular opening 188 and walls 190 sloped to the samedegree as the conical wall of the first socket 172 a. The second socket172 b can conveniently have the same transverse cross-section as thefirst socket, as shown in FIG. 20. The second pin 166 and the widthdimension of the second socket 172 b are sized and shaped so as toaccommodate the second pin 166 b in the second socket 172 b in the samemanner as with the first pin 166 a and first socket 172 a. The lengthdimension is large enough to allow relative translation of the secondpin 166 along the second socket 172 b. This accommodates variations infirst to second socket dimensions from pallet to pallet.

The second socket 172 b is obstructed by the free end 168 of the secondpin 166 b from translating in a direction parallel to the width of thesecond socket 172 and is unobstructed to translational repositioning ina direction paralleling the length of the second socket 172 b, withinthe limits of the ends of the second socket 172 b. The second socket 172b is unobstructed for rotation about the second mount axis 180b andabout the cross-track and travel axes 182,184 through a hemispherecentered on the second mount axis 180 b, while in engagement with thesecond pin 166 b.

Referring now particularly to FIGS. 20-28, the first and secondpin-socket pairs 173 a,173 b are spaced apart and thus block rotation ofa pallet 11 about an axis 192 extending perpendicular to a line 194connecting the centers of the two pin-socket pairs 173 a,173 b. Rotationof the pallet 11 about the line connecting the centers of the twopin-socket pairs 173 a,173 b is not blocked. In the embodiments shown inFIGS. 23-24 and 26 the line connecting the two pin-socket pairs 173a,173 b parallels the travel axis 184 or the cross-track axis 182,respectively; and rotation about one of the axes 182,184, respectively,is blocked. It is preferred, as shown in FIGS. 23-24, that the lengthdimension of the second socket 172 b and the line connecting the centersof the first and second pin-socket pairs 173 a,173 b are colinear andparallel to the travel axis. This configuration allows the length of thesecond socket 172 b to accommodate variability in the relative positionsof the two pin-socket pairs 173 a, 173 b; but constrains the second pin166 b within the width dimension of the second socket 172 b.

It is more preferred that the first and second mounts 174 are located,one behind the other, on the same rail. This places the length dimensionof the second socket 172 parallel with the travel axis 184 and thelongest dimension of the rails 134,136 and reduces the width of railneeded to accommodate the first and second mounts 174 a, 174 b. Thesecond socket 172 b is obstructed by second pin 166 b from translatingalong the cross-track axis and is unobstructed to translationalrepositioning in a direction parallel to the travel axis, within thelimits of the ends of the second socket 172 b. In this embodiment, thefirst and second pins 166 a,166 b, do not block the pallet from rotationabout the travel axis.

The third socket 172 c can be a flat pad and the third pin 166 c a posthaving a flattened free end 168, as shown in FIG. 22A, or ahemispherical free end 168 as in the first and second pins 166 a, 166 bdescribed above (not separately illustrated). Alternatively, the thirdpin 166 c can be gimballed to the bolster 124, as shown in FIG. 22B. Inthis case, the third pin 166 c has a rod portion 165 that terminates ina hemisphere and a pad portion 167 that pivotably receives thehemisphere of the rod portion 165.

The third socket 172 c is unobstructed by the third pin 166 c fromtranslating in a plane defined by the cross-track and travel axes182,184. The third socket 172 c is capable of rotation about the thirdmount axis 180 c and rotation about the cross-track and travel axes182,184 through a hemisphere centered on the third mount axis 180 c.Relative rotation of the free end 168 of the third pin 166 and the thirdsocket 172 c is biased against by frictional forces and gravity.

The sockets 172 are sized to provide sufficient clearance for themovement of the free ends 168. The sockets 172 can be made asreplaceable inserts fitted in the pallet bodies and can be made of asofter material than the pins 166 to shift wear away from the pins 166to the more easily replaceable inserts. The sockets 172 can be made towear away over a predetermined range during use, since the wear is notcritical to the positioning of the pallet 11 in the raised position.

In use, workpieces 12 are subjected to initial operations and are thendelivered with pallets 11 to the entry buffer 85 of the apparatus 10.Operations are performed on the workpieces 12 in the apparatus 10 andthe workpieces 12 are delivered with the pallets 11 for removal orfurther operations. Operations within the main chamber 18 of theapparatus 10 are synchronous. Other operations, including transport, canbe synchronous or asynchronous. This allows great flexibility inconnecting the apparatus 10 with other manufacturing stations 196. Forexample, FIG. 29 illustrates a manufacturing system 198 havingasynchronous manufacturing operations performed manually at threestations 196 followed by asynchronous transport on a conveying system199 to the apparatus 10 and from the apparatus 10 to an off-feed station200. FIG. 30 illustrates a manufacturing system 198 having manualstations 196 feeding into a transport loop 202 that selectively feedsready units alternately, to a pair of apparatus 10 arranged in parallel.Both apparatus 10 feed to an off-feed station 200 and return path 204.FIG. 31 illustrates a manufacturing system 198 similar to that of FIG.30, but with multiple manual stations 196 on each of a series of feederloops 202 and multiple off-feed stations 200. FIG. 31 illustratesanother branching arrangement for a manufacturing system 198 havingmultiple apparatus 10. The manufacturing systems 198 are illustratedwith manual stations. Individual automated stations are interchangeablewith the manual stations. The apparatus 10 are illustrated used inparallel. The apparatus 10 can also be arranged sequentially one behindanother, with a synchronous or asynchronous connection betweenindividual apparatus 10.

Referring now particularly to FIG. 6, in a particular embodiment of theinvention, the apparatus 10 is divided into three separate modules: aentry module 206, a main module 208, and an exit module 210. Each module206,208,210 is readily transportable without further disassembly. Theentry module 206 has an entry housing 212 including the entry chamber 20and optionally including a connecting tunnel 23. The entry housing 212is supported by a secondary support 214 independent of the tablesupport. An entry conveyor 25 is disposed in the entry chamber 20. Astub conveyor 29 extends within the connecting tunnel 23. The exitmodule 210 is like the entry module 206. The main module 208 includesthe remaining components of the apparatus 10, including the main chamber18, the table base 32, the table 28, the bolster 124 and locating units128, and the transporter 64. These components can be left in place inthe main module 208 when it is transported. In the illustratedembodiments, the main module 208 has the overall configuration of arectangular box. The box can easily be sized to fit in the requirementsof a truck trailer or shipping container. Work devices 48 are optionallyalso portable with the other components of the main module 208 withoutdisassembly.

The transfer apparatus and registration mechanism are not limited to theembodiments above described. For example, pallet transport for theregistration mechanism can be varied. FIG. 44 illustrates an apparatus216 in which the registration mechanism has a transporter 64 that is awalking beam unit 64 a. The walking beam unit 64 a includes a palletsupport 218, a walking beam drive unit 220, and one or morereciprocating arms 222. The arm or arms 222 are driven by the drive unit220, as indicated by arrow 224, so as to drive the support about anellipsoidal path. The support 218 is attached to the arms 222 and, likeother walking beam transport apparatus known to those of skill in theart, provides both an up and down movement of the pallets 11 and anadvance movement of the pallets from station to station. The up and downmovement can be limited by a stop 227 that holds the support duringparts of cycles. If necessary, seats 225 or other means can be providedon the support to grip the pallets 11 during advancing. (The pallets 11would have matching pegs (not shown) or other grip features.) Since thesupport 218 acts as a walking beam, only the pallets 11 and not thesupport 218 advance past the datum units 36. The walking beam unit isnot used to lift the pallets against the datum units. Like the beltmechanism earlier discussed, only a moderate degree of accuracy andprecision is required for the walking beam unit, since transporter wearor misalignment has to be gross to effect registration accuracy andprecision. Suitable features of walking beam movements are well known tothose of skill in the art. The bolster 124 operates in the same manneras described for other embodiments, except that the pallets 11 arelifted off the support 218. The registration mechanism is otherwise asearlier described.

FIG. 45 illustrates another embodiment of the transfer apparatus, inwhich the data pads 38 are continuous and the locating units each have apair of cylindrical pins 228 that fit in matching holes 230 in thepallet 11 a. A third support is provided by a fixed bushing pad 232 andmatching pallet surface 234. The transfer apparatus is otherwise asearlier described. While usable, this approach requires tightertolerances than the other embodiments earlier discussed.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention.

What is claimed is:
 1. A registration mechanism comprising: a datum unit; a bolster segment-pallet pair having a bolster aligned with said datum unit and a pallet disposed between said datum unit and said bolster, said bolster segment-pallet pair having first, second, and third sockets and first, second, and third mounts facing respective said sockets, said mounts defining parallel, first, travel and cross-track mount axes, said pallet having a registering face facing said datum unit, said bolster segment-pallet pair being movable between a lowered position wherein said registering face is spaced apart from said datum unit and a raised position wherein said registering face is in registration with said datum unit; and first, second, and third pins supported by said bolster, said pins supporting said pallet, said pins each having a fixed end joined to and restrained from lateral movement by a respective said mount, said pins each having a free end engaging a respective said socket, said free end of said first pin obstructing said first socket from translating along orthogonal travel and cross-track axes perpendicular to said first mount axis, said free end of said first pin allowing rotation of said first socket about said first mount axis and through a hemisphere centered on said first mount axis, said free end of said second pin obstructing said second socket from translating perpendicular to said travel axis, said second socket being unobstructed from translational repositioning along a segment of said travel axis, said second socket being rotatable relative to said free end of said second pin through a hemisphere centered on said second mount axis, said third socket being unobstructed by said third pin from translating along said travel and cross-track axes.
 2. The mechanism of claim 1 wherein said pallet is removable from said pins.
 3. The mechanism of claim 1 wherein said bolster segment-pallet pair is movable between said lowered position and said raised position in a direction parallel to said mount axes.
 4. The mechanism of claim 1 wherein said pins are resiliently biased outward from respective said mounts.
 5. The mechanism of claim 1 wherein said bolster and pins clamp said pallet against said datum unit in said raised position.
 6. The mechanism of claim 1 said datum unit has opposed registration and alignment faces, and said registering face is clamped against said registration face in said raised position.
 7. The mechanism of claim 1 wherein said first pin has a hemispherical tip in engagement with said first socket.
 8. The mechanism of claim 7 wherein said second pin has a hemispherical tip and said second socket is an elongate notch sized to closely receive said second pin tip.
 9. The mechanism of claim 8 wherein said third pin is a post having a flattened end and said third socket is a flat pad.
 10. A registration mechanism comprising: a datum unit; a bolster movable toward and away from said datum unit; first, second, and third pins mounted to said bolster; at least one spring resiliently biasing said pins outward from said bolster; a pallet supported by said pins between said bolster and said datum unit, said pallet having first, second, and third sockets aligned with respective said first, second, and third pins, said pallet having a registering face facing said datum unit, said registering face being disposed opposite said sockets, said pallet being movable by said bolster toward said datum unit: from a lowered position, wherein said registering face is spaced from said datum unit and respective said pins and sockets are spaced apart, through a first intermediate position, wherein said registering face is spaced from said datum unit, and said sockets rest freely on respective said pins, then through a second intermediate position, wherein respective said sockets and pins are pressed together in partial counteraction of said resilient biasing, to a raised position, wherein said registering face and said datum unit are clamped together and said sockets are immobilized relative to said pins; wherein said first pin defines a first mount axis and said first socket is obstructed by said first pin from translating along orthogonal travel and cross-track axes perpendicular to said first mount axis, said first socket being rotatable relative to a free end of said first pin through a hemisphere centered on said first mount axis.
 11. A registration mechanism comprising: a datum unit; a bolster movable toward and away from said datum unit; first, second, and third pins mounted to said bolster; at least one spring resiliently biasing said pins outward from said bolster; a pallet supported by said pins between said bolster and said datum unit, said pallet having first, second, and third sockets aligned with respective said first, second, and third pins, said pallet having a registering face facing said datum unit, said registering face being disposed opposite said sockets, said pallet being movable by said bolster toward said datum unit: from a lowered position, wherein said registering face is spaced from said datum unit and respective said pins and sockets are spaced apart, through a first intermediate position, wherein said registering face is spaced from said datum unit, and said sockets rest freely on respective said pins, then through a second intermediate position, wherein respective said sockets and pins are pressed together in partial counteraction of said resilient biasing, to a raised position, wherein said registering face and said datum unit are clamped together and said sockets are immobilized relative to said pins; wherein said second pin defines a second mount axis, said second socket is unobstructed by said second pin from translational repositioning along a segment of a travel axis perpendicular to said second mount axis and is obstructed by said second pin from translating along a cross-track axis perpendicular to said travel axis and second mount axis, said second socket being rotatable relative to a free end of said second pin through a hemisphere centered on said second mount axis, said third socket being unobstructed by a free end of said third pin from translating along said travel and cross-track axes.
 12. A registration mechanism comprising: a datum unit; a bolster movable toward and away from said datum unit; a plurality of locating units mounted to said bolster, each said locating units having first, second, and third pins; at least one spring resiliently biasing said pins outward from said bolster; a plurality of pallets supported by said locating units, said pallets each having first, second, and third sockets aligned with said first, second, and third pins of a respective said locating unit, said pallet having a registering face facing said datum unit, said registering face being disposed opposite said sockets, said pallet being movable by said bolster toward said datum unit: from a lowered position, wherein said registering face is spaced from said datum unit and respective said pins and sockets are spaced apart, through a first intermediate position, wherein said registering face is spaced from said datum unit, and said sockets rest freely on respective said pins, then through a second intermediate position, wherein respective said sockets and pins are pressed together in partial counteraction of said resilient biasing, to a raised position, wherein said registering face and said datum unit are clamped together and said sockets are immobilized relative to said pins; wherein said first pin has a hemispherical tip in engagement with said first socket; and wherein said second pin has a hemispherical tip and said second socket is an elongate notch sized to closely receive said second pin tip.
 13. The mechanism of claim 12 wherein said third pin is a post having a flattened end and said third socket is a flat pad.
 14. A registration mechanism comprising: a table having a datum unit and a component support, said datum unit being immobile relative to said component support; a bolster movable toward and away from said datum unit along a mount axis; first, second, and third pins, said pins each having a fixed end joined to and restrained from lateral movement by said bolster, said pins each having a free end opposite the respective said fixed end; at least one spring resiliently biasing said pins outward from said bolster; a pallet supported by said pins between said bolster and said datum unit, said pallet having first, second, and third sockets engaging said free ends of respective said first, second, and third pins, said pallet having a registering face facing said datum unit, said registering face being disposed opposite said sockets, said first socket being cup-shaped and having the same dimension along orthogonal travel and cross-track axes perpendicular to said mount axis, said second socket being trough-shaped and having a width dimension along said cross-track axis shorter than a length dimension along said travel axis, said third socket being flat.
 15. A registration mechanism comprising: a datum unit; a bolster movable toward and away from said datum unit first, second, and third pins mounted to said bolster; at least one spring resiliently biasing said pins outward from said bolster; a pallet disposed between said bolster and said datum unit, said pallet having first, second, and third sockets aligned with respective said first, second, and third pins, said first pin defining a first mount axis, said pallet being movable by said bolster toward said datum unit: from a lowered position, wherein respective said pins and sockets are spaced apart, through a sequence of intermediate positions, wherein said sockets initially rest freely on respective said pins and are then pressed together in partial counteraction of said biasing, to a raised position, wherein said sockets are immobilized relative to said pins, said first socket, in said intermediate positions, being obstructed by said first pin from translating along orthogonal travel and cross-track axes perpendicular to said first mount axis, said first socket, in said intermediate positions, being rotatable relative to said first pin through a hemisphere centered on said first mount axis.
 16. The mechanism of claim 15 wherein said second pin has a hemispherical tip and said second socket is an elongate notch sized to closely receive said second pin tip.
 17. The mechanism of claim 16 wherein said third pin is a post having a flattened end and said third socket is a flat pad.
 18. The mechanism of claim 15 wherein said third pin is a post having a flattened end and said third socket is a flat pad.
 19. The mechanism of claim 15 wherein said second pin defines a second mount axis, said second socket is unobstructed by said second pin from translational repositioning along a segment of a travel axis perpendicular to said second mount axis and is obstructed by said second pin from translating along a cross-track axis perpendicular to said travel and second mount axes, said second socket being rotatable relative to said second pin through a hemisphere centered on said second mount axis.
 20. The mechanism of claim 19 wherein said third socket is unobstructed by said third pin from translating along said travel and cross-track axes.
 21. The mechanism of claim 19 wherein said first pin has a hemispherical tip in engagement with said first socket.
 22. The mechanism of claim 19 wherein said third pin is a post having a flattened end and said third socket is a flat pad.
 23. A registration mechanism comprising: a datum unit; a bolster movable toward and away from said datum unit; first, second, and third pins mounted to said bolster; at least one spring resiliently biasing said pins outward from said bolster; a pallet disposed between said bolster and said datum unit, said pallet having first, second, and third sockets aligned with respective said first, second, and third pins, said second pin defining a second mount axis, said pallet being movable by said bolster toward said datum unit: from a lowered position, wherein respective said pins and sockets are spaced apart, through a sequence of intermediate positions, wherein said sockets initially rest freely on respective said pins and are then pressed together in partial counteraction of said biasing, to a raised position, wherein said sockets are immobilized relative to said pins, said second socket being unobstructed by said second pin from translational repositioning along a segment of a travel axis perpendicular to said second mount axis and obstructed by said second pin from translating along a cross-track axis perpendicular to said travel and second mount axes, said second socket being rotatable relative to said second pin through a hemisphere centered on said second mount axis, said third socket being unobstructed by said third pin from translating along said travel and cross-track axes.
 24. The mechanism of claim 23 wherein said first pin has a hemispherical tip in engagement with said first socket.
 25. The mechanism of claim 24 wherein said third pin is a post having a flattened end and said third socket is a flat pad. 